Add tests for registerCollapsibleNavHeader warning console output

Signed-off-by: Yulong Ruan <[email protected]>

src/core/public/chrome/chrome_service.test.ts

@@ -109,6 +109,10 @@ afterAll(() => {
 });
 
 describe('setup', () => {
+  afterEach(() => {
+    jest.restoreAllMocks();
+  });
+
   it('register custom Nav Header render', async () => {
     const customHeaderMock = React.createElement('TestCustomNavHeader');
     const renderMock = jest.fn().mockReturnValue(customHeaderMock);
@@ -122,6 +126,24 @@ describe('setup', () => {
     expect(wrapper.prop('collapsibleNavHeaderRender')).toBeDefined();
     expect(wrapper.prop('collapsibleNavHeaderRender')()).toEqual(customHeaderMock);
   });
+
+  it('should output warning message if calling `registerCollapsibleNavHeader` more than once', () => {
+    const warnMock = jest.fn();
+    jest.spyOn(console, 'warn').mockImplementation(warnMock);
+    const customHeaderMock = React.createElement('TestCustomNavHeader');
+    const renderMock = jest.fn().mockReturnValue(customHeaderMock);
+    const chrome = new ChromeService({ browserSupportsCsp: true });
+
+    const chromeSetup = chrome.setup();
+    // call 1st time
+    chromeSetup.registerCollapsibleNavHeader(renderMock);
+    // call 2nd time
+    chromeSetup.registerCollapsibleNavHeader(renderMock);
+    expect(warnMock).toHaveBeenCalledTimes(1);
+    expect(warnMock).toHaveBeenCalledWith(
+      '[ChromeService] An existing custom collapsible navigation bar header render has been overridden.'
+    );
+  });
 });
 
 describe('start', () => {